Joint for tubular metal furniture frames



July 15, 1952 M. GREITZER JOINT FOR TUBULAR METAL FURNITURE FRAMES Filgd Oct. 22, 1948 I INVENTOR- //YE7 fizz-v 72252 By I Patented July 15, 1952 U p,STAT

' JOINT FOR TUBULAR FURNITURE FRAMES 1 Meyer Grci tzer, Los AngeleaCalif. I" Application October 22, 1948, Serial No.-55,990 1 claim. (01. '2'S7- 1'195" v My invention relates to a joint structure for metal tubes, particularly those tubes used in the production of chairs and like articles of furniture, and the principal object of my invention is to provide a joint for metal tubing which is simple in structure, inexpensive of production, having a high degree of strength and stability, and which is capable of being easily and quickly disconnected when the assembled parts are knocked down for storage and transportation.

A further object of my invention is to provide a joint of the character referred to which may be readily connected and disconnected without the requirement of special tools, wrenches, pliers or the like, and the joint, when properly connected, presenting a neat and finished appearance.

With the foregoing and other objects in view, my invention consists in certain novel features of construction and arrangement of parts which will be hereinafter more fully described and claimed and illustrated in the accompanying drawing, in which:

Fig. 1 is a front elevational view of the upper portion of a metal frame chair and with my improved joints in the upright-back supporting members.

Fig. 2 is an enlarged vertical section taken on the line 2-2 of Fig. 1.

Fig. 3 is a horizontal section taken on the line 3-3 of Fig. 2.

Fig. 4 is a horizontal section taken on the line 44 of Fig. 2.

Fig. 5 is a vertical section similar to Fig. 2 and showing a modified form of the joint.

Fig. 6 is a horizontal section taken on the line 66 of Fig. 5.

Referring by numerals to the accompanying drawing, particularly Figs. 1 to 4, inclusive, II] V designates the front legs of a tubular metal chair frame, II the chair seat, I2 short upright tubular frame members at the rear of the seat frame, I3 upright tubular back supporting members which are detachably connected to members I2 by my improved joints and I3a, the chair back. Surrounding the adjacent ends of members I2 and I3 are collars or short sleeves I4, each having an internal circumferential flange I5 which fits snugly between the ends of the corresponding tubes I2 and I3.

Suitably secured by screws or otherwise in the upper portion of each member I3, is a plug I6 of metal, plastics or the like, provided in lower portion with an axial bore I1 and in its upper portion with a smaller bore I8.

Fitting snugly in bore I8 is the upper portion of vide a finger 2 I, which projects through a notch 22 formed in the lower end portion of plug I6 and into an aperture 23, formed in the wall of tube I2. Thus arm I9 provides a resilient hook that serves to latch and secure tubes I2 and I3 to each other. To assemble the joint, tubes I2 and I3 are fitted into collar I4, with their ends bearing on flange I5, with finger 2I seated in aperture 23, thus providing a firm and substantial connection between tubes I2 and I3, with no portion of the latching means other than the end of finger 2|, exposed on the exterior of the joint. To disconnect the joint, it is only necessary to push finger inwardly until it clears aperture 22, thus enabling tube I3 to be withdrawn from collar I l and upper portion of plug I6.

In the modified form of joint shown in Figs. 5 and 6, the abutting ends of tubes 25 are seated in a ferrule or sleeve 26, and disposed within the adjacent ends of said tubes is a resilient arm 21, one end of which is suitably secured to the wall of one of said tubes and the free end of said arm carrying on its outer face a stud 28 adapted to enter a short horizontally disposed slot 29 formed in the wall of the adjacent tube.

In this form of joint, sleeve 26 is suitably secured by screws, rivets or welding to one of the tubes 25, preferably the one to which arm 21 is secured.

To disconnect this form of joint, it is only necessary to push pin 28 inwardly out of slot 29 and then pull the tubes 25 apart. While my improved joint is especially designed for detachably connecting parts of tubular metal chair frames, it may be used with equal advantage in connecting tubes of various structures where a strong, compact and readily connected and disconnected joint is required.

The tubular joint structure herein disclosed is an improvement which may be advantageously employed in the chairs disclosed in my co-pending patent applications filed June 30, 1945, Ser. No. 602,531, now Patent Number 2,461,055, issued February 8, 1949, and Ser. No. 768,452, filed August 13, 1947, now Patent #2,525,126, issued October 10, 1950, also Patent #2,306,878, issued December 29, 1942, to me, the assignee of Morris Greitzer.

Thus it will be seen that I have provided a tube joint that is simple in structure, inexpensive of manufacture and very effective in performing the functions for which it is intended.

Minor changes in the size, form and construction of the various parts of my improved tube joint maybe made and substituted for those herein shown and described, without departing from the spirit of my invention, the scope of which is set forth in the appended claim.

I claim as my invention:

In a ,tubularjoint construction, the ,combinaticn with a pair of aligned tubes spaced slightly apart, of a plug secured within one of said tubes and projecting into the other, said plug beingprovided throughout its length with an axial bore, and at one end with asmaller'bore, ithe end of the plug having said axial bore being provided with a notch, with the end of the tube into which said plug projects provided withan aperture registering with said notchfa springllatchhaving one end secured in the smallerbore in REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 534,434 Frost Feb. 19, 1895 1,770,852 Hill July 15, 1930 ,2ii46;4()6 :Beyerle Aug. 3, 1948 2,473,388 Rambo June 14, 1949 

